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Feedback Stabilization over Wireless Network Using Adaptive Coded Modulation 被引量:5
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作者 Li Yang Xin-Ping Guan +1 位作者 Cheng-Nian Long Xiao-Yuan Luo 《International Journal of Automation and computing》 EI 2008年第4期381-388,共8页
In this paper,we apply adaptive coded modulation (ACM) schemes to a wireless networked control system (WNCS) to improve the energy efficiency and increase the data rate over a fading channel.To capture the characteris... In this paper,we apply adaptive coded modulation (ACM) schemes to a wireless networked control system (WNCS) to improve the energy efficiency and increase the data rate over a fading channel.To capture the characteristics of varying rate, interference,and routing in wireless transmission channels,the concepts of equivalent delay (ED) and networked condition index (NCI) are introduced.Also,the analytic lower and upper bounds of EDs are obtained.Furthermore,we model the WNCS as a multicontroller switched system (MSS) under consideration of EDs and loss index in the wireless transmission.Sufficient stability condition of the closed-loop WNCS and corresponding dynamic state feedback controllers are derived in terms of linear matrix inequality (LMI). Numerical results show the validity and advantage of our proposed control strategies. 展开更多
关键词 Wireless networked control system (WNCS) adaptive coded modulation (ACM) equivalent delay (ed) networked condition index (NCI) multicontroller switched system (MSS) stability.
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Performance evaluation of laterite soil embankment stabilized with bottom ash,coir fiber,and lime
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作者 Yunusa Hamdanu SANI Amin EISAZADEH 《Journal of Mountain Science》 SCIE CSCD 2024年第7期2334-2351,共18页
In tropical regions,heavy rainfall induces erosion and shallow landslides on road embankments.Cement-based stabilization methods,common in these regions,contribute to climate change due to their high carbon footprint.... In tropical regions,heavy rainfall induces erosion and shallow landslides on road embankments.Cement-based stabilization methods,common in these regions,contribute to climate change due to their high carbon footprint.This study explored the potential application of coir fiber-reinforced laterite soil-bottom ash mixtures as embankment materials in the tropics.The objective is to enhance engineered embankment slopes'erosion resistance and stability while offering reuse options for industrial byproducts.This study examined various mix designs for unconfined compressive strength(UCS)and permeability,utilizing 30%bottom ash(BA)and 1%coir fiber(CF)with varying sizes ranging from 10 to 40 mm,6%lime,and laterite soil(LS),followed by microstructural analyses.The results demonstrate that the compressive strength increases as the CF length increases to 25 mm.In contrast,permeability increases continuously with increasing CF length.Lime-treated mixtures exhibit superior short-and long-term strength and reduce permeability owing to the formation of cementitious materials,as confirmed by microstructural analyses.A lab-scale slope box was constructed to evaluate the surface erosion of the stabilized laterite soil embankment.Based on the rainfall simulation results,the LS-BA-CF mixtures show better resistance to erosion and deformation compared to untreated LS,especially when lime is added to the top layer.This study provides insights into a sustainable and cost-effective approach for slope stabilization using BA and CF,offering a promising solution for tropical regions susceptible to surface erosion and landslides. 展开更多
关键词 Lateritic soil Bottom ash Coir fiber LIME Unconfined compressive strength PERMEABILITY FESEM/edS Rainfall simulation tests
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降压药能与抗ED药物同服吗
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作者 毕瑞 《漫科学(新健康)》 2024年第1期30-31,共2页
高血压作为一种最常见的心血管疾病,与勃起功能障碍(ED)有着密切的联系。根据美国马萨诸塞州男性老年化研究资料显示,在40~70岁男性当中有超过一半的人受到不同程度ED的困扰,年发病率为124/1000。同时据流行病学研究发现,ED在非高血压... 高血压作为一种最常见的心血管疾病,与勃起功能障碍(ED)有着密切的联系。根据美国马萨诸塞州男性老年化研究资料显示,在40~70岁男性当中有超过一半的人受到不同程度ED的困扰,年发病率为124/1000。同时据流行病学研究发现,ED在非高血压人群中发生率为16%;在高血压人群中,发病率则高达32.1%,远高于正常血压人群。那为什么高血压容易并发ED呢?原因主要有以下3点。 展开更多
关键词 正常血压 流行病学研究 高血压人群 老年化 心血管疾病 美国马萨诸塞州 降压药 ed
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从精英到公众的开放资源:TED的发展及启示 被引量:29
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作者 洪岩 梁林梅 《现代教育技术》 CSSCI 2013年第4期12-15,共4页
作为全球开放教育资源运动的成功案例,2006年以来TED以其独特的发展模式和全新的共享理念异军突起,在极短的时间内就迅速成为全球OER领域备受瞩目的焦点。论文首先介绍了TED的起源和发展,接着对TED独特的运作和组织机制进行了分析,并对... 作为全球开放教育资源运动的成功案例,2006年以来TED以其独特的发展模式和全新的共享理念异军突起,在极短的时间内就迅速成为全球OER领域备受瞩目的焦点。论文首先介绍了TED的起源和发展,接着对TED独特的运作和组织机制进行了分析,并对TED的成功经验进行了评述,最后提出了对我国开放教育资源发展的几点启示。 展开更多
关键词 Ted Tedx Ted-ed 开放教育资源 网络社区
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Application of Special Controlled Release Fertilizer in Direct-seeding of Rapeseeds 被引量:2
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作者 范连益 黄晓勤 +2 位作者 惠荣奎 朱飞翔 邓力超 《Agricultural Science & Technology》 CAS 2015年第4期745-749,共5页
In the east of Hunan Province, the research introduced new-type special controI ed-reIease fertiIizer for rapeseed, "Yishizhuang", and expIored its appIications in direct-seeding of rapeseed production. The resuIts ... In the east of Hunan Province, the research introduced new-type special controI ed-reIease fertiIizer for rapeseed, "Yishizhuang", and expIored its appIications in direct-seeding of rapeseed production. The resuIts showed that the appIication of special controI ed reIease fertiIizer for rapeseeds avoids earIy decIine of rapeseed resuIting from fertiIizer Ioss by one-off appIication, improves the number of green Ieaf before winter, and extends photosynthetic Iifespan of pods, which significantIy increases yields. What&#39; more, with higher output-input ratio, the fertiIizer takes ad-vantages in saving cost, Iabor and increasing yield. 展开更多
关键词 RAPESEed ControI ed release fertliizer Formula fertliizer Direct seeding
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基于Edge Drawing的工业图像圆检测算法
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作者 杨庆五 罗小辉 刘鑫 《计算机与现代化》 2024年第11期121-126,共6页
针对基于Hough变换类圆检测算法所需的参数较多和计算量较大的问题,本文提出一种实时的、无参数的圆检测算法。该算法通过利用ED(Edge Drawing)算法得到图像中的若干边缘片段,并通过线段检测器从边缘片段几何中提取可能构成圆的圆弧线... 针对基于Hough变换类圆检测算法所需的参数较多和计算量较大的问题,本文提出一种实时的、无参数的圆检测算法。该算法通过利用ED(Edge Drawing)算法得到图像中的若干边缘片段,并通过线段检测器从边缘片段几何中提取可能构成圆的圆弧线段集合。对每一对线段进行分析,判断是否可以形成一对有效线段,从而生成初始的圆集合。接下来依据圆边缘的几何属性生成候选圆并采用反向验证原理进行验证。实验结果表明,该方法在图像中的圆存在模糊、阴影和遮挡等干扰下仍有较好的检测效果,并且相较于其他算法,在工业图像上的精度和稳定性得到显著提高。 展开更多
关键词 圆检测 极性分析 ed 圆拟合 区域约束
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A dual-RPA based lateral flow strip for sensitive,on-site detection of CP4-EPSPS and Cry1Ab/Ac genes in genetically modified crops 被引量:1
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作者 Jinbin Wang Yu Wang +7 位作者 Xiuwen Hu Yifan Chen Wei Jiang Xiaofeng Liu Juan Liu Lemei Zhu Haijuan Zeng Hua Liu 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期183-190,共8页
Traditional transgenic detection methods require high test conditions and struggle to be both sensitive and efficient.In this study,a one-tube dual recombinase polymerase amplification(RPA)reaction system for CP4-EPSP... Traditional transgenic detection methods require high test conditions and struggle to be both sensitive and efficient.In this study,a one-tube dual recombinase polymerase amplification(RPA)reaction system for CP4-EPSPS and Cry1Ab/Ac was proposed and combined with a lateral flow immunochromatographic assay,named“Dual-RPA-LFD”,to visualize the dual detection of genetically modified(GM)crops.In which,the herbicide tolerance gene CP4-EPSPS and the insect resistance gene Cry1Ab/Ac were selected as targets taking into account the current status of the most widespread application of insect resistance and herbicide tolerance traits and their stacked traits.Gradient diluted plasmids,transgenic standards,and actual samples were used as templates to conduct sensitivity,specificity,and practicality assays,respectively.The constructed method achieved the visual detection of plasmid at levels as low as 100 copies,demonstrating its high sensitivity.In addition,good applicability to transgenic samples was observed,with no cross-interference between two test lines and no influence from other genes.In conclusion,this strategy achieved the expected purpose of simultaneous detection of the two popular targets in GM crops within 20 min at 37°C in a rapid,equipmentfree field manner,providing a new alternative for rapid screening for transgenic assays in the field. 展开更多
关键词 Genetically modifi ed crops On-site detection Lateral fl ow test strips Dual recombinase polymerase amplification (RPA)
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EDS成分分析法在电气熔痕鉴定中的应用
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作者 赵富胜 刘璇 《山东化工》 CAS 2024年第8期167-169,共3页
EDS成分分析法是微量物证鉴定的常用方法,具有灵敏度高、操作简单快速等特点,在纤维、金属、玻璃、油漆及纸张等各类微量物证的鉴定中有着广泛的应用。在火灾痕迹物证鉴定领域,EDS成分分析法已成为重要方法之一。通过探讨三起采用EDS成... EDS成分分析法是微量物证鉴定的常用方法,具有灵敏度高、操作简单快速等特点,在纤维、金属、玻璃、油漆及纸张等各类微量物证的鉴定中有着广泛的应用。在火灾痕迹物证鉴定领域,EDS成分分析法已成为重要方法之一。通过探讨三起采用EDS成分分析法对电气熔痕进行鉴定的实例,提出在火灾现场物证取样、熔痕鉴定和鉴定意见运用等方面的注意事项。 展开更多
关键词 X射线能谱仪 edS成分分析法 电气熔痕鉴定
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给定控制数的连通图的最大EDS极图
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作者 杨丽英 雷勇 《吕梁学院学报》 2024年第2期8-10,共3页
图G的偏心距离和(EDS)定义为ξ^(d)(G)=∑_(v∈V)ε_(G)(v)D_(G)(v),其中ε_(G)(v)是顶点v的偏心率,D_(G)(v)是顶点v到G中其它所有顶点的距离之和.通过研究图的EDS,给出了Miao等猜想的一个更简单的证明,确定了给定控制数的连通图的最大... 图G的偏心距离和(EDS)定义为ξ^(d)(G)=∑_(v∈V)ε_(G)(v)D_(G)(v),其中ε_(G)(v)是顶点v的偏心率,D_(G)(v)是顶点v到G中其它所有顶点的距离之和.通过研究图的EDS,给出了Miao等猜想的一个更简单的证明,确定了给定控制数的连通图的最大EDS极图. 展开更多
关键词 控制数 连通控制数 edS
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Outstanding proton conductivity over wide temperature and humidity ranges and enhanced mechanical, thermal stabilities for surface-modified MIL-101-Cr-NH_(2)/Nafion composite membranes
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作者 Xu Li Dongwei Zhang +7 位作者 Si Chen Yingzhao Geng Yong Liu Libing Qian Xi Chen Jingjing Li Pengfei Fang Chunqing He 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第11期1734-1746,共13页
High-performance proton exchange membranes are of great importance for fuel cells.Here,we have synthesized polycarboxylate plasticizer modified MIL-101-Cr-NH_(2)(PCP-MCN),a kind of hybrid metal-organic framework,which ... High-performance proton exchange membranes are of great importance for fuel cells.Here,we have synthesized polycarboxylate plasticizer modified MIL-101-Cr-NH_(2)(PCP-MCN),a kind of hybrid metal-organic framework,which exhibits a superior proton conductivity.PCP-MCN nanoparticles are used as additives to fabricate PCP-MCN/Nafion composite membranes.Microstructures and characteristics of PCP-MCN and these membranes have been extensively investigated.Significant enhancement in proton conduction for PCP-MCN around 55℃ is interestingly found due to the thermal motion of the PCP molecular chains.Robust mechanical properties and higher thermal decomposition temperature of the composite membranes are directly ascribed to strong intermolecular interactions between PCP-MCN and Nafion side chains,i.e.,the formation of substantial acid–base pairs(-SO_(3)^(-)…^(+)H–NH-),which further improves compatibility between additive and Nafion matrix.At the same humidity and temperature condition,the water uptake of composite membranes significantly increases due to the incorporation of porous additives with abundant functional groups and thus less crystallinity degree in comparison to pristine Nafion.Proton conductivity(σ)over wide ranges of humidities(30-100%RH at 25℃)and temperatures(30-98℃ at 100%RH)for prepared membranes is measured.The s in PCPMCN/Nafion composite membranes is remarkably enhanced,i.e.0.245 S/cm for PCP-MCN-3wt.%/Nafion is twice that of Nafion membrane at 98℃ and 100%RH,because of the establishment of well-interconnected proton transport ionic water channels and perhaps faster protonation–deprotonation processes.The composite membranes possess weak humidity-dependence of proton transport and higher water uptake due to excellent water retention ability of PCP-MCN.In particular,when 3 wt.%PCP-MCN was added to Nafion,the power density of a single-cell fabricated with this composite membrane reaches impressively 0.480,1.098 W/cm^(2) under 40%RH,100%RH at 60℃,respectively,guaranteeing it to be a promising proton exchange membrane. 展开更多
关键词 Nafion composite membrane Surface-modified MIL-101-Cr-NH_(2) Proton conductivity Single-cell performance
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Thermo-Mechanical, Physico-Chemical, Morphological, and Fire Characteristics of Eco-Friendly Particleboard Manufactured with Phosphorylated Lignin Addition
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作者 Apri Heri Iswanto Harisyah Manurung +14 位作者 Asma Sohail Lee Seng Hua Petar Antov Deded Sarip Nawawi Sarah Latifah Dewi Shafa Kayla Sukma Surya Kusumah Muhammad Adly Rahandi Lubis Linda MakovickáOsvaldová MohdHazwan Hussin Rangabhashiyam Selvasembian Lum Wei Chen Puji Rahmawati Nurcahyani Nam Hun Kim Widya Fatriasari 《Journal of Renewable Materials》 EI CAS 2024年第7期1311-1341,共31页
Lignin,lignosulfonate,and synthesized phosphorylated lignosulfonate were introduced as greenfillers in citric acid-sucrose adhesives for bonding particleboard fabricated from areca leaf sheath(ALS).The characteristics ... Lignin,lignosulfonate,and synthesized phosphorylated lignosulfonate were introduced as greenfillers in citric acid-sucrose adhesives for bonding particleboard fabricated from areca leaf sheath(ALS).The characteristics of particleboards were compared to that of ultralow emitting formaldehyde(ULEF-UF).Thefillers derived from Eucalyptus spp.kraft-lignin were added forflame retardancy enhancement.10%of each lignin and modified lig-nin was added into the ULEF-UF and citric acid-sucrose bonded particleboards.Analyses applied to particle-boards included thermal characteristics,X-ray diffraction analysis(XRD),morphological properties,Fourier transform infrared spectroscopy(FTIR),as well as physical,mechanical,andfire resistance characteristics of the laboratory-fabricated particleboards.Lignin and modified lignin resulted in improved thermal stability of the composites bonded with ULEF-UF while the improvement in the particleboard bonded with citric acid-sucrose was not significant.The introduction offiller exerted a higher influence on the UF-bonded particleboards compared to composites fabricated with citric acid-sucrose.Generally,the presence of lignin,lignosulfonate,and phosphorylated lignosulfonate enhanced the mechanical strength of the ULEF-bonded particleboards,although their dimensional stability has deteriorated.Markedly,the use of lignin and lignosulfonate enhanced thefire resis-tance of the particleboards produced with lower observed weight loss.All laboratory particleboards exhibited satisfactoryfire resistance,attaining a V-0 rating in according to the UL-94 standard. 展开更多
关键词 Modified lignin eco-friendly particleboard fire and thermal properties citric acid-sucrose ultralow-emitting urea-formaldehyde resin
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智能变电站IEC 61850 Ed 2.0工程配置应用方案 被引量:17
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作者 李金 胡荣 +1 位作者 王丽华 王志华 《电力系统自动化》 EI CSCD 北大核心 2018年第2期154-159,共6页
IEC 61850第2版(Ed 2.0)对系统集成配置过程进行了重大改进,包括新增实例化的智能电子设备描述(instantiated IED description,IID)文件和系统交换描述(SED)文件,加强配置工具约束,引入分项目管理方法。论文根据当前智能变电站IEC 6185... IEC 61850第2版(Ed 2.0)对系统集成配置过程进行了重大改进,包括新增实例化的智能电子设备描述(instantiated IED description,IID)文件和系统交换描述(SED)文件,加强配置工具约束,引入分项目管理方法。论文根据当前智能变电站IEC 61850工程配置实际需求,对IEC 61850Ed 2.0工程配置过程改进的工程实用性进行深入分析。提出IEC 61850Ed 2.0配置过程工程化应用方案,包括变电站配置描述(SCD)文件配置过程改进方案和工程分项目管理方案,并给出典型应用示例。 展开更多
关键词 IEC 61850 ed 2.0 配置调试过程 分项目管理 IID文件 Sed文件
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SEM-EDS结合结垢趋势模拟软件在反渗透膜污堵原因分析中的应用
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作者 殷明威 吴家琛 马兴峰 《给水排水》 CSCD 北大核心 2024年第3期82-86,共5页
回用水系统中,反渗透膜的污堵问题经常发生。而污堵的原因常常难以确定,进而导致无法从根本上解决污堵问题。详细阐述了先利用SEM-EDS分析反渗透膜微观结构污堵情况和污堵物元素分布,确定污堵物主要成分,再利用结垢趋势模拟软件模拟出... 回用水系统中,反渗透膜的污堵问题经常发生。而污堵的原因常常难以确定,进而导致无法从根本上解决污堵问题。详细阐述了先利用SEM-EDS分析反渗透膜微观结构污堵情况和污堵物元素分布,确定污堵物主要成分,再利用结垢趋势模拟软件模拟出反渗透系统最佳运行条件,从而解决反渗透膜污堵问题的过程和方法。从实际应用案例来看,SEM-EDS结合结垢趋势模拟软件可以快速准确的找到膜系统污堵原因,并从根本上解决污堵问题。 展开更多
关键词 SEM-edS 结垢趋势模拟 反渗透膜 污堵原因
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AED:一种用于DTN的增强型Earliest-Delivery算法 被引量:14
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作者 周晓波 卢汉成 +1 位作者 李津生 洪佩琳 《电子与信息学报》 EI CSCD 北大核心 2007年第8期1956-1960,共5页
DTN(Delay-Tolerant Network)是人们在近年出现的众多网络实例中抽象出来的网络模型。在这种网络模型中,经常出现长时间的网络分割,以至于在给定的时间段内端到端的路径不一定存在。由于DTN这种独特的拓扑性质,其路由机制和传统的网络... DTN(Delay-Tolerant Network)是人们在近年出现的众多网络实例中抽象出来的网络模型。在这种网络模型中,经常出现长时间的网络分割,以至于在给定的时间段内端到端的路径不一定存在。由于DTN这种独特的拓扑性质,其路由机制和传统的网络模型有很大不同。该文详细研究了DTN的一种路由算法ED(Earliest-Delivery)算法,然后引入了对节点运动精确性(相对于时间)的考虑,给出了精确性因子p(Δ)的定义,并以之作为ED算法中"链接"(contact)1)代价的权重,进而提出一种更稳健的路由算法——AED(Advanced ED)。实验表明,当节点运动不确定性增加时,AED维持较好的性能,而ED的性能则明显下降。 展开更多
关键词 DTN 路由算法 ORACLE ed Aed 时间精确性
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在RHEED实时监控下GaAs晶体生长研究 被引量:9
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作者 罗子江 周勋 +4 位作者 杨再荣 贺业全 何浩 邓朝勇 丁召 《功能材料》 EI CAS CSCD 北大核心 2010年第4期704-708,共5页
采用分子束外延技术,利用RHEED图像可研究GaAs表面重构方式和生长机制。报道了一种新型的分子束外延方法,在RHEED实时监控下,利用GaAs(001)基片同质外延GaAs。通过改变生长和退火的时间与温度(420、500、580℃),结合RHEED图像演变与GaA... 采用分子束外延技术,利用RHEED图像可研究GaAs表面重构方式和生长机制。报道了一种新型的分子束外延方法,在RHEED实时监控下,利用GaAs(001)基片同质外延GaAs。通过改变生长和退火的时间与温度(420、500、580℃),结合RHEED图像演变与GaAs表面平整度(粗糙化)的联系,得到表面原子级平整的GaAs样品。完成生长后对样品做EDS分析,确定样品为高纯度GaAs。利用这种方法,得到厚度约为4μm砷化镓晶体。 展开更多
关键词 MBE RHEed图像 粗糙化 edS GaAs表面重构
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带有—ed成分的英语复合词概览
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作者 李迢澎 《伊犁教育学院学报》 2002年第3期65-67,共3页
在为数可观的英语复合词中,带有一ed成分的复合词占有相当的比重,与其结合的有名词、形容词、副词和数词等。并对这类复合词的构成形式和语法功能值得探讨。
关键词 英语复合词 "名词+ed"形式 "形容词+ed"形式 "副词+ed"形式 "数词+ed"形式 语法功能
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无痛胃镜检查时布托啡诺抑制吞咽反射ED50和ED95的测定 被引量:7
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作者 胡君凤 胡双燕 +4 位作者 仲俊峰 叶钢 毛琳玲 邱凯 陈栋樑 《中国内镜杂志》 2022年第2期63-67,共5页
目的测定不同剂量丙泊酚复合布托啡诺无痛胃镜检查时,布托啡诺抑制吞咽反射的ED50和ED95值。方法将76例无痛胃镜检查患者随机分为P1组和P2组,P1组给予丙泊酚2.0 mg/kg复合布托啡诺静脉麻醉,P2组给予2.5 mg/kg丙泊酚复合布托啡诺静脉麻... 目的测定不同剂量丙泊酚复合布托啡诺无痛胃镜检查时,布托啡诺抑制吞咽反射的ED50和ED95值。方法将76例无痛胃镜检查患者随机分为P1组和P2组,P1组给予丙泊酚2.0 mg/kg复合布托啡诺静脉麻醉,P2组给予2.5 mg/kg丙泊酚复合布托啡诺静脉麻醉。布托啡诺初始剂量为5.0μg/kg,根据吞咽反射抑制情况,运用Dixon序贯法确定下一例患者使用剂量,应用Probit分析得出两组患者布托啡诺抑制吞咽反射ED50和ED95值。结果P2组低血压发生率明显高于P1组(P<0.05);P1组和P2组布托啡诺抑制吞咽反射的ED50分别为3.5μg/kg(95%CI:2.9~4.1)和3.1μg/kg(95%CI:2.4~3.5);P1组和P2组抑制吞咽反射的ED95分别为5.8μg/kg(95%CI:4.7~15.9)和5.0μg/kg(95%CI:4.1~12.3)。结论布托啡诺复合丙泊酚2.0和2.5 mg/kg无痛胃镜检查时,抑制吞咽反射的ED50分别为3.5和3.1μg/kg,ED95分别为5.8和5.0μg/kg,对临床无痛胃镜麻醉用药具有指导意义。 展开更多
关键词 布托啡诺 ed50 ed95 胃镜 吞咽反射
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能量色散X射线荧光光谱法(ED-XRF)测定粗硒中的硒含量
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作者 周明俊 张胜 《广州化工》 CAS 2024年第2期170-172,186,共4页
针对容量法和重量法测定粗硒中硒含量过程中存在的流程长、操作繁琐等问题,本文考察了不同的压样条件,调整压力以及添加不同比例的纤维素、硼酸和碳酸锂等,最终选择采用碳酸锂作为混合剂,将粗硒粉末样品和碳酸锂粉末按照比例1∶1混匀,... 针对容量法和重量法测定粗硒中硒含量过程中存在的流程长、操作繁琐等问题,本文考察了不同的压样条件,调整压力以及添加不同比例的纤维素、硼酸和碳酸锂等,最终选择采用碳酸锂作为混合剂,将粗硒粉末样品和碳酸锂粉末按照比例1∶1混匀,然后在压样机上用10 t压力压制成测试样片,并考察了测试样片的均匀性。在选定的工作条件下,采用能量色散X射线荧光光谱仪(ED-XRF)建立工作曲线,可以实现对粗硒中硒含量的定量测定,同时将测定结果与容量法测定结果进行对比,结果一致。本方法快速准确。 展开更多
关键词 粗硒 碳酸锂 ed-XRF 定量分析
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Pathogenesis and treatment of diabetes mellitus-related erectile dysfunction: current therapies and potential challenges
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作者 Han-Yu He# Fan-Yu Meng +4 位作者 Huan-Tian Cui Jun-Yu Luo Si-Qi Ma Wei-Bo Wen Jie Zhao 《Clinical Research Communications》 2024年第2期11-17,共7页
Erectile dysfunction(ED)is one of the important complications of diabetes,which is very common in diabetic patients,affecting more than half of male patients,and the incidence of the disease is about 3.5 times that of... Erectile dysfunction(ED)is one of the important complications of diabetes,which is very common in diabetic patients,affecting more than half of male patients,and the incidence of the disease is about 3.5 times that of the normal population.The pathogenesis of diabetic erectile dysfunction(DMED)is complex,involving nerve,vascular,endocrine,muscular and psychological aspects.At present,the therapeutic approaches of DMED include drug therapy,surgery,physical therapy and so on.This article provides a review of current research on the pathogenesis and treatment of DMED.Further elucidation of the pathogenesis of DMED and the development of new therapeutic approaches are of great significance for the prevention and treatment of DMED. 展开更多
关键词 diabetes mellitus(DM) erectile dysfunction(ed) PATHOGENESIS THERAPIES
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Determination of Egg Shell Structure and Mineral Composition Using SEM-EDS and Identification the Possibility to Produce Fertilizer
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作者 Purevjav Urjintseren Jargalsaikhan Byambaa 《Journal of Materials Science and Chemical Engineering》 2024年第3期21-30,共10页
Throwing out egg shells without using them depreciates a vital source of calcium. As an egg shell contains twice the amount of calcium a person needs a day, it is considered as the richest source of calcium of natural... Throwing out egg shells without using them depreciates a vital source of calcium. As an egg shell contains twice the amount of calcium a person needs a day, it is considered as the richest source of calcium of natural origin. Egg shells have been traditionally and widely used in medicine, beauty science and food production for decades. In spite of that, there is a lack of new solutions that profoundly study mineral elements and beneficial components contained in egg shells for further usage as a product. Assuming we consume 2 eggs a day, the yearly consumption for a person is 730 eggs. As beneficial component, the egg shell structure and mineral elements, were determined in 3 types of samples (Mongolian eggs, Russian eggs, and iodized eggs) by SEM-EDS (Scanning electron microscopy with energy dispersive spectroscopy), a state-of-the-art research method. Consequently, it was established that egg shells consists of Ca (72.6% - 85.7%), Mg (2.7% - 4.5%), Si (0.3% - 0.6%), P (7.0% - 18.1%), S (0.5% - 2.0%), K (0.4% - 0.9%), I (2.6% - 3.0%), respectively. Additionally, the D3.8 × 120, 250, 500, and 1000 times zoomed images of shell structure (SEM) of each sample were examined, and the results were compared and evaluated. The reverse titration method examination has demonstrated that the calcium carbonate (CaCO<sub>3</sub>) content in egg shells is 91% - 92.5%, and pH is 8.41 - 8.75. Ultimately, fertilizer containing 97.7% Ca without chemical additives has been extracted by grounding the eggshells to 4.4 μm, then preparing the mixture at the rate of 20:0.5 (shell: mix, enriched with mandarin and lemon peel) and adjusting its pH to 7.5 - 8.0. Further research on the impact of fertilizer on growing process of indoor flowers has been commenced. 展开更多
关键词 SEM-edS Analysis Calcium Carbonate Organic Fertilizer
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